Biotin-binding protein and their derivatives can be widely used in various applications. However, production or purification of recombinant biotin-binding proteins can be very difficult. When expressed in E. coli, most biotin-binding proteins tend to accumulate in inclusion bodies, denaturing, refolding and tedious downstream processing are required in the preparation of active proteins. Expression in E. coli is preferable because of the low cost of production and the potential for further engineering; thus, biotin-binding proteins that can be efficiently produced in E. coli are highly sought after. Further, expression E. coli also provides the possibility to generate recombinant fusion proteins containing biotin-binding protein for various applications.
Accordingly, there is need in the art for biotin-binding proteins and fusion proteins containing biotin-binding proteins which can be expressed in soluble form in high yields in E. coli. 